Microorganisms are widely used for industrially producing a broad range of useful substances, including alcoholic beverages, certain types of foods such as miso (i.e., fermented soybean paste) and shoyu (i.e., soy sauce), amino acids, organic acids, nucleic-acid-related substances, antibiotics, sugars, lipids, and proteins. These substances also find diversified uses, including foods, pharmaceuticals, detergents, products for daily use such as cosmetics, and a variety of chemical raw materials.
In industrial production of useful substances by use of microorganisms, improvement of productivity is one major topic of interest, and one approach therefor is breeding of microorganisms through mutagenesis or other genetic means. Recently, in particular, with advancement of microbial genetics and biotechnology, more efficient production of useful substances through gene recombination techniques attracts attention.
Studies on promoters necessary for gene transcription have heretofore been actively conducted. For example, in relation to Bacillus subtilis, as a promoter region which is useful in achieving powerful transcription of a gene encoding a heterologous protein or polypeptide, there have been utilized a promoter region of an alkaline cellulase gene originating from Bacillus sp. KSM-64 (FERM BP-2886) (see, for example, Non-Patent Document 1) and a promoter region which is found in an upstream site of an alkaline cellulase gene originating from Bacillus sp. KSM-S237 (FERM BP-7875).
However, in production on an industrial scale, reduction in production cost is necessary, and higher productivity is demanded, because the above-mentioned promoter regions currently in use do not necessarily promise sufficiently enhanced productivity.    Patent Document 1: JP-A-2000-210081    Non-Patent Document 1: Biosci. Biotech. Biochem., 59, 2172, (1995)